Color support (#1630)

docs/changelog/1630.feature.rst

@@ -0,0 +1,2 @@
+Add option to disable colored output, and support ``NO_COLOR`` and ``FORCE_COLOR`` environment variables - by
+:user:`gaborbernat`.

setup.cfg

@@ -42,6 +42,7 @@ install_requires =
     toml>=0.10
     virtualenv>=20.0.20
     importlib-metadata>=1.6.0;python_version<"3.8"
+    typing-extensions>=3.7.4.2;python_version<"3.8"
 python_requires = >=3.6
 package_dir =
     =src

src/tox/config/cli/parse.py

@@ -9,15 +9,15 @@ def get_options(*args) -> Tuple[Parsed, List[str], Dict[str, Handler]]:
     guess_verbosity = _get_base(args)
     handlers, parsed, unknown = _get_core(args)
     if guess_verbosity != parsed.verbosity:
-        setup_report(parsed.verbosity)  # pragma: no cover
+        setup_report(parsed.verbosity, parsed.is_colored)  # pragma: no cover
     return parsed, unknown, handlers
 
 
 def _get_base(args):
     tox_parser = ToxParser.base()
     parsed, unknown = tox_parser.parse(args)
     guess_verbosity = parsed.verbosity
-    setup_report(guess_verbosity)
+    setup_report(guess_verbosity, parsed.is_colored)
     return guess_verbosity
 
 

src/tox/config/cli/parser.py

@@ -1,9 +1,12 @@
 import argparse
 import logging
+import os
+import sys
 from argparse import SUPPRESS, Action, ArgumentDefaultsHelpFormatter, ArgumentParser, Namespace
 from itertools import chain
 from typing import Any, Callable, Dict, List, Optional, Sequence, Tuple, Type, TypeVar
 
+from tox.config.source.ini import StrConvert
 from tox.plugin.util import NAME
 from tox.session.state import State
 
@@ -42,8 +45,16 @@ def fix_default(self, action: Action) -> None:
     def get_type(action):
         of_type = getattr(action, "of_type", None)
         if of_type is None:
-            # noinspection PyProtectedMember
-            if action.default is not None:
+            if isinstance(action, argparse._StoreAction) and action.choices:  # noqa
+                loc = locals()
+                if sys.version_info >= (3, 8):
+                    from typing import Literal  # noqa
+                else:
+                    from typing_extensions import Literal  # noqa
+                loc["Literal"] = Literal
+                as_literal = f"Literal[{', '.join(repr(i) for i in action.choices)}]"
+                of_type = eval(as_literal, globals(), loc)
+            elif action.default is not None:
                 of_type = type(action.default)
             elif isinstance(action, argparse._StoreConstAction) and action.const is not None:  # noqa
                 of_type = type(action.const)
@@ -71,6 +82,10 @@ class Parsed(Namespace):
     def verbosity(self) -> int:
         return max(self.verbose - self.quiet, 0)
 
+    @property
+    def is_colored(self) -> True:
+        return self.colored == "yes"
+
 
 Handler = Callable[[State], Optional[int]]
 
@@ -121,12 +136,20 @@ def _add_base_options(self) -> None:
         verbosity_group = self.add_argument_group(
             f"verbosity=verbose-quiet, default {logging.getLevelName(LEVELS[3])}, map {level_map}",
         )
-        verbosity_exclusive = verbosity_group.add_mutually_exclusive_group()
-        verbosity_exclusive.add_argument(
-            "-v", "--verbose", action="count", dest="verbose", help="increase verbosity", default=2,
-        )
-        verbosity_exclusive.add_argument(
-            "-q", "--quiet", action="count", dest="quiet", help="decrease verbosity", default=0,
+        verbosity = verbosity_group.add_mutually_exclusive_group()
+        verbosity.add_argument("-v", "--verbose", action="count", dest="verbose", help="increase verbosity", default=2)
+        verbosity.add_argument("-q", "--quiet", action="count", dest="quiet", help="decrease verbosity", default=0)
+
+        converter = StrConvert()
+        if converter.to_bool(os.environ.get("NO_COLOR", "")):
+            color = "no"
+        elif converter.to_bool(os.environ.get("FORCE_COLOR", "")):
+            color = "yes"
+        else:
+            color = "yes" if sys.stdout.isatty() else "no"
+
+        verbosity_group.add_argument(
+            "--colored", default=color, choices=["yes", "no"], help="should output be enriched with colors",
         )
         self.fix_defaults()
 

src/tox/config/source/api.py

@@ -1,10 +1,16 @@
+import sys
 from abc import ABC, abstractmethod
 from collections import OrderedDict
 from pathlib import Path
 from typing import Any, Dict, List, Sequence, Set, Union
 
 from tox.execute.request import shell_cmd
 
+if sys.version_info >= (3, 8):
+    from typing import Literal
+else:
+    from typing_extensions import Literal
+
 _NO_MAPPING = object()
 
 
@@ -39,7 +45,8 @@ def __iter__(self):
 
 class Convert(ABC):
     def to(self, raw, of_type):
-        if getattr(of_type, "__module__", None) == "typing":
+        from_module = getattr(of_type, "__module__", None)
+        if from_module in ("typing", "typing_extensions"):
             return self._to_typing(raw, of_type)
         elif issubclass(of_type, Path):
             return self.to_path(raw)
@@ -54,7 +61,7 @@ def to(self, raw, of_type):
         return of_type(raw)
 
     def _to_typing(self, raw, of_type):
-        origin = getattr(of_type, "__origin__", None)
+        origin = getattr(of_type, "__origin__", getattr(of_type, "__class__", None))
         if origin is not None:
             result = _NO_MAPPING  # type: Any
             if origin in (list, List):
@@ -72,6 +79,14 @@ def _to_typing(self, raw, of_type):
                     else:
                         new_type = next(i for i in of_type.__args__ if i != type(None))  # noqa
                         result = self._to_typing(raw, new_type)
+            elif origin == Literal or origin == type(Literal):
+                if sys.version_info >= (3, 7):
+                    choice = of_type.__args__
+                else:
+                    choice = of_type.__values__
+                if raw not in choice:
+                    raise ValueError(f"{raw} must be one of {choice}")
+                result = raw
             if result is not _NO_MAPPING:
                 return result
         raise TypeError(f"{raw} cannot cast to {of_type!r}")

src/tox/config/source/ini/__init__.py

@@ -170,7 +170,7 @@ def _load_raw_from(self, as_name, conf, key):
         if self._section is None:
             raise KeyError(key)
         value = self._section[key]
-        collapsed_newlines = value.replace("\\\n", "")  # collapse explicit line splits
+        collapsed_newlines = value.replace("\\\r", "").replace("\\\n", "")  # collapse explicit line splits
         replace_executed = replace(collapsed_newlines, conf, as_name, self._section_loader)  # do replacements
         factor_selected = filter_for_env(replace_executed, as_name)  # select matching factors
         # extend factors

src/tox/config/source/ini/convert.py

@@ -13,6 +13,7 @@ def to_path(value):
     @staticmethod
     def to_list(value):
         splitter = "\n" if "\n" in value else ","
+        splitter = splitter.replace("\r", "")
         for token in value.split(splitter):
             value = token.strip()
             if value:
@@ -48,7 +49,7 @@ def to_env_list(value):
         return EnvList(elements)
 
     TRUTHFUL_VALUES = {"true", "1", "yes", "on"}
-    FALSY_VALUES = {"false", "0", "no", "off"}
+    FALSY_VALUES = {"false", "0", "no", "off", ""}
     VALID_BOOL = list(sorted(TRUTHFUL_VALUES | FALSY_VALUES))
 
     @staticmethod

src/tox/execute/api.py

@@ -103,13 +103,13 @@ def __init__(self, outcome: Outcome, exc: KeyboardInterrupt):
 
 
 class Execute(ABC):
-    def __call__(self, request: ExecuteRequest, show_on_standard: bool) -> Outcome:
+    def __call__(self, request: ExecuteRequest, show_on_standard: bool, colored: bool) -> Outcome:
         start = timer()
         executor = self.executor()
         interrupt = None
         try:
             with CollectWrite(sys.stdout if show_on_standard else None) as out:
-                with CollectWrite(sys.stderr if show_on_standard else None, Fore.RED) as err:
+                with CollectWrite(sys.stderr if show_on_standard else None, Fore.RED if colored else None) as err:
                     instance = executor(request, out.collect, err.collect)  # type: ExecuteInstance
                     try:
                         exit_code = instance.run()

src/tox/pytest.py

@@ -1,6 +1,7 @@
 import os
 import sys
 import textwrap
+from contextlib import contextmanager
 from pathlib import Path
 from typing import Any, Callable, Dict, List, Optional, Sequence
 
@@ -23,6 +24,7 @@ def ensure_logging_framework_not_altered():
     LOGGER.handlers = before_handlers
 
 
+@contextmanager
 def check_os_environ():
     old = os.environ.copy()
     to_clean = {k: os.environ.pop(k, None) for k in {ENV_VAR_KEY, "TOX_WORK_DIR", "PYTHONPATH"}}
@@ -51,7 +53,16 @@ def check_os_environ():
         pytest.fail(msg)
 
 
-check_os_environ_stable = pytest.fixture(autouse=True)(check_os_environ)
+@pytest.fixture(autouse=True)
+def check_os_environ_stable(monkeypatch):
+    with check_os_environ():
+        yield
+        monkeypatch.undo()
+
+
+@pytest.fixture(autouse=True)
+def no_color(monkeypatch, check_os_environ_stable):
+    monkeypatch.setenv("NO_COLOR", "yes")
 
 
 @pytest.fixture(name="tox_project")

src/tox/report.py

@@ -33,7 +33,7 @@ def _get_formatter(level):
         return formatter
 
 
-def setup_report(verbosity):
+def setup_report(verbosity, is_colored):
     _clean_handlers(LOGGER)
     level = _get_level(verbosity)
     LOGGER.setLevel(level)
@@ -42,7 +42,8 @@ def setup_report(verbosity):
     LOGGER.addHandler(handler)
 
     logging.debug("setup logging to %s", logging.getLevelName(level))
-    init()
+    if is_colored:
+        init()
 
 
 def _get_level(verbosity):

src/tox/tox_env/api.py

@@ -126,7 +126,7 @@ def execute(
             show_on_standard = self.options.verbosity > 3
         request = ExecuteRequest(cmd, cwd, self.environment_variables, allow_stdin)
         self.logger.warning("run => %s$ %s", request.cwd, request.shell_cmd)
-        outcome = self._executor(request=request, show_on_standard=show_on_standard)
+        outcome = self._executor(request=request, show_on_standard=show_on_standard, colored=self.options.colored)
         self.logger.info("done => code %d in %s for  %s", outcome.exit_code, outcome.elapsed, outcome.shell_cmd)
         return outcome
 

src/tox/tox_env/builder.py

@@ -40,12 +40,11 @@ def _run(self) -> None:
             )
 
     def _build_run_env(self, env_conf: ConfigSet, env_name):
-        # noinspection PyUnresolvedReferences
         env_conf.add_config(
             keys="runner",
             desc="the tox execute used to evaluate this environment",
             of_type=str,
-            default=self.options.default_runner,
+            default=self.options.default_runner,  # noqa
         )
         runner = cast(str, env_conf["runner"])
         from .register import REGISTER

src/tox/tox_env/python/virtual_env/runner.py

@@ -78,9 +78,8 @@ def package_env_name_type(self):
 
     def install_package(self):
         package = self.package_env.perform_packaging()
-        self.install_python_packages(
-            package, no_deps=True, develop=self.conf["package"] is PackageType.dev, force_reinstall=True,
-        )
+        develop = self.conf["package"] is PackageType.dev
+        self.install_python_packages(package, no_deps=True, develop=develop, force_reinstall=True)
 
 
 @impl

tests/unit/config/cli/test_cli_env_var.py

@@ -16,6 +16,7 @@ def test_verbose_compound(monkeypatch):
 def test_verbose_no_test_skip_missing(monkeypatch):
     parsed, _, __ = get_options("--notest", "-vv", "--skip-missing-interpreters", "false", "--runner", "virtualenv")
     assert vars(parsed) == {
+        "colored": "no",
         "verbose": 4,
         "quiet": 0,
         "command": "run",
@@ -39,11 +40,12 @@ def test_env_var_exhaustive_parallel_values(monkeypatch, core_handlers):
 
     parsed, unknown, handlers = get_options()
     assert vars(parsed) == {
+        "colored": "no",
         "verbose": 5,
         "quiet": 1,
         "command": "run-parallel",
         "env": ["py37", "py36"],
-        "default_runner": "magic",
+        "default_runner": "virtualenv",
         "recreate": True,
         "no_test": True,
         "parallel": 3,

tests/unit/config/cli/test_cli_ini.py

@@ -16,11 +16,12 @@ def exhaustive_ini(tmp_path: Path, monkeypatch: MonkeyPatch):
         textwrap.dedent(
             """
         [tox]
+        colored = yes
         verbose = 5
         quiet = 1
         command = run-parallel
         env = py37, py36
-        default_runner = magic
+        default_runner = virtualenv
         recreate = true
         no_test = true
         parallel = 3
@@ -49,6 +50,7 @@ def empty_ini(tmp_path: Path, monkeypatch: MonkeyPatch):
 def test_ini_empty(empty_ini, core_handlers):
     parsed, unknown, handlers = get_options()
     assert vars(parsed) == {
+        "colored": "no",
         "verbose": 2,
         "quiet": 0,
         "command": "run",
@@ -65,11 +67,12 @@ def test_ini_empty(empty_ini, core_handlers):
 def test_ini_exhaustive_parallel_values(exhaustive_ini, core_handlers):
     parsed, unknown, handlers = get_options()
     assert vars(parsed) == {
+        "colored": "yes",
         "verbose": 5,
         "quiet": 1,
         "command": "run-parallel",
         "env": ["py37", "py36"],
-        "default_runner": "magic",
+        "default_runner": "virtualenv",
         "recreate": True,
         "no_test": True,
         "parallel": 3,
@@ -100,6 +103,7 @@ def test_bad_cli_ini(tmp_path: Path, monkeypatch: MonkeyPatch, caplog):
     )
     assert caplog.messages == [f"failed to read config file {tmp_path} because {msg}"]
     assert vars(parsed) == {
+        "colored": "no",
         "verbose": 2,
         "quiet": 0,
         "command": "run",
@@ -130,6 +134,7 @@ def test_bad_option_cli_ini(tmp_path: Path, monkeypatch: MonkeyPatch, caplog, va
         ),
     ]
     assert vars(parsed) == {
+        "colored": "no",
         "verbose": 2,
         "quiet": 0,
         "command": "run",

tests/unit/config/cli/test_parser.py

@@ -1,4 +1,6 @@
-from tox.config.cli.parser import ToxParser
+import pytest
+
+from tox.config.cli.parser import Parsed, ToxParser
 
 
 def test_parser_const_with_default_none(monkeypatch):
@@ -16,3 +18,29 @@ def test_parser_const_with_default_none(monkeypatch):
 
     result, _ = parser.parse([])
     assert result.alpha == 2
+
+
+@pytest.mark.parametrize("is_atty", [True, False])
+@pytest.mark.parametrize("no_color", [None, "0", "1"])
+@pytest.mark.parametrize("force_color", [None, "0", "1"])
+@pytest.mark.parametrize("tox_color", [None, "bad", "no", "yes"])
+def test_parser_color(monkeypatch, mocker, no_color, force_color, tox_color, is_atty):
+    for key, value in {"NO_COLOR": no_color, "TOX_COLORED": tox_color, "FORCE_COLOR": force_color}.items():
+        if value is None:
+            monkeypatch.delenv(key, raising=False)
+        else:
+            monkeypatch.setenv(key, value)
+    stdout_mock = mocker.patch("tox.config.cli.parser.sys.stdout")
+    stdout_mock.isatty.return_value = is_atty
+
+    if tox_color in ("yes", "no"):
+        expected = True if tox_color == "yes" else False
+    elif no_color == "1":
+        expected = False
+    elif force_color == "1":
+        expected = True
+    else:
+        expected = is_atty
+
+    is_colored = ToxParser.base().parse_args([], Parsed()).is_colored
+    assert is_colored is expected